Aktis Oncology, Inc.

Aktis Oncology, Inc. is a clinical-stage oncology company focused on expanding targeted radiopharmaceuticals to a broad range of cancer patient populations, particularly those not addressed by existing platform technologies. The company aims to develop next-generation technologies to broaden the scope of tumor targets for safe delivery of alpha-emitting radioisotopes and establish an efficient end-to-end supply chain. The global radiopharmaceuticals market is projected to grow to over $26 billion ⁷ in sales by 2032, with the therapeutic segment estimated to achieve a total addressable market of $25 billion to $60 billion ⁸ post-2030.

The company has built a proprietary miniprotein radioconjugate platform designed to selectively deliver tumor-killing radioisotopes with high tumor penetration and prolonged tumor retention, while rapidly clearing from normal organs to minimize systemic radiation exposure. Miniproteins are polypeptides of less than one hundred amino acids, with the company prioritizing those 40 to 70 amino acids in length, which are classified as biologics from a regulatory perspective, providing a twelve-year exclusivity period for approved products. This platform enables the engineering of potent, precision miniprotein-based radioconjugates that bind to tumor cell surface targets.

Aktis Oncology's core business model revolves around the discovery, development, and potential commercialization of novel miniprotein radioconjugates for oncology. Revenue generation is currently primarily through collaboration agreements, such as the one with Eli Lilly, which provided a $60.0 million ¹⁰ upfront cash payment. The company's primary customer segments, if products are approved, would be patients with various solid tumors, with a focus on expanding beyond traditional nuclear medicine into broader clinical oncology settings. The company's platform dynamics involve leveraging its miniprotein technology for both imaging isotopes to select patients and therapeutic isotopes to treat tumors, enabling a theranostic approach.

The most advanced product candidate is [225 Ac]Ac-AKY-1189, a miniprotein radioconjugate targeting Nectin-4 expressing tumors, including locally advanced or metastatic urothelial cancer (UC), breast cancer, non-small cell lung cancer (NSCLC), colorectal cancer, and cervical cancer. Nectin-4 is a clinically validated oncology target, also targeted by Padcev, an antibody-drug conjugate, which had worldwide sales of $1.9 billion ⁴ in 2024 and estimated peak sales of up to $7.0 billion ⁵. [225 Ac]Ac-AKY-1189 is in a multi-site Phase 1b clinical trial in the United States, with preliminary results from the Part-1 dose escalation anticipated in the first quarter of 2027 ⁶. The miniprotein AKY-1189 has a binding affinity (K D) to Nectin-4 of 0.22 nanomolar (nM) ¹¹ and an inhibitory constant (K i) of 0.82 nM ¹² to Nectin-4 expressing tumor cells.

The second most advanced program is [225 Ac]Ac-AKY-2519, targeting B7-H3 expressing solid tumors such as prostate, lung, and breast cancers. B7-H3 is highly expressed in approximately 90% ¹³ of metastatic castration-resistant prostate cancers, 80% ¹⁴ of NSCLCs, and 70% ¹⁵ of small cell lung cancers. Preclinical studies of [225 Ac]Ac-AKY-2519 demonstrated dose-dependent antitumor activity, with 92% ¹⁶ tumor growth inhibition for the 1.0 µCi dose and 80% ¹⁷ for the 0.5 µCi dose in NSCLC xenograft models. The company expects to initiate a multi-site Phase 1b clinical trial for [225 Ac]Ac-AKY-2519 in mid-2026 ¹⁸.

For the fiscal year ended December 31, 2025, Aktis Oncology reported net losses of $63.7 million ¹⁹. As of December 31, 2025, the company had an accumulated deficit of $156.6 million ²⁰ and $226.8 million ²¹ in cash, cash equivalents, and marketable securities. The company has not generated any revenues from product sales to date.

The net losses for the year ended December 31, 2025, increased to $63.7 million ¹⁹ from $44.0 million ²² in 2024, reflecting a substantial increase in expenses. This indicates a significant year-over-year increase in operating losses as the company advances its research and development programs.

Significant operational developments during the period include the FDA clearance of the investigational new drug (IND) application for [225 Ac]Ac-AKY-1189 in April 2025 ²³, leading to the commencement of a multi-site Phase 1b clinical trial in the United States. In December 2025 ²⁴, the company completed the first dose level of the Part 1 dose escalation for this trial and began enrollment for the next dose level. Additionally, [225 Ac]Ac-AKY-1189 was granted Fast Track Designation by the FDA in February 2026 ²⁵ for locally advanced or metastatic UC. The INDs for [225 Ac]Ac-AKY-2519 and [64 Cu]Cu-AKY-2519 were cleared by the FDA in March 2026 ²⁶. The company also entered into a discovery collaboration with Eli Lilly and Company in May 2024 ⁹, receiving a $60.0 million ¹⁰ upfront cash payment and an equity investment. The Minnesota License was terminated in July 2025 ²⁷, with an effective termination date of September 9, 2025 ²⁸.

Management anticipates that preliminary results from the Part-1 dose escalation portion of the Phase 1b clinical trial for [225 Ac]Ac-AKY-1189 will be available in the first quarter of 2027 ⁶. The company expects to initiate the multi-site Phase 1b clinical trial for [225 Ac]Ac-AKY-2519 in mid-2026 ¹⁸. No formal revenue, margin, or EPS guidance for the upcoming period was explicitly stated in the filing.

A major growth area for Aktis Oncology is the advancement of its lead product candidate, [225 Ac]Ac-AKY-1189, for Nectin-4 expressing tumors. This includes locally advanced or metastatic UC, breast cancer, NSCLC, colorectal cancer, and cervical cancer. The company believes the commercial impact of Padcev, which targets Nectin-4 and had worldwide sales of $1.9 billion ⁴ in 2024 with estimated peak sales of up to $7.0 billion ⁵, validates Nectin-4 as an anticancer target. The Phase 1b trial for [225 Ac]Ac-AKY-1189 will enroll approximately 150 patients ²⁹ and, upon completion of dose escalation, will include dose expansion cohorts in locally advanced or metastatic UC (n=30) ³⁰, triple-negative breast cancer (n=30) ³¹, and a basket cohort of other Nectin-4 expressing tumors (n=40) ³². The company plans to seek alignment with the FDA for a pivotal Phase 2 trial for accelerated approval of [225 Ac]Ac-AKY-1189.

Another significant growth vector is the development of [225 Ac]Ac-AKY-2519 for B7-H3 expressing tumors, including prostate, lung, and breast cancers. B7-H3 is highly expressed in approximately 90% ¹³ of metastatic castration-resistant prostate cancers, 80% ¹⁴ of NSCLCs, and 70% ¹⁵ of small cell lung cancers. The company expects to report results of imaging and dosimetry assessments for [68 Ga]Ga-AKY-2519 and [177 Lu]Lu-AKY-2519 in patients with various B7-H3 expressing solid tumors in mid-2026 ³³. The planned Phase 1b program for [225 Ac]Ac-AKY-2519 will enroll patients with mCRPC, NSCLC, or small cell lung cancer.

Operationally, Aktis Oncology is focused on investing in manufacturing and ensuring supply chain continuity and reliability. The company is establishing its own current Good Manufacturing Practice (cGMP) facility, which is expected to be fully operational in the second half of 2026 ³⁴. This facility aims to enhance flexibility, increase control, and establish a hybrid internal and external clinical supply chain. The company also has partnerships with multiple domestic and international isotope suppliers, including NorthStar Medical Technologies, LLC, TerraPower Isotopes, LLC, and Niowave, Inc., to provide priority access to 225 Ac.

The company's planned capital allocation includes continued investment in research and development programs, particularly advancing [225 Ac]Ac-AKY-1189 through clinical trials and [225 Ac]Ac-AKY-2519 into clinical trials. The Eli Lilly collaboration provides for potential milestone payments up to an additional $1.2 billion ³⁵ upon achievement of preclinical, clinical, regulatory, and commercial milestones, as well as tiered royalties of up to 10% ³⁶ based on annual net sales. The company also received $10.0 million ³⁷ from an equity investment by Eli Lilly in Series A-1 redeemable convertible preferred stock.

Management explicitly flagged several structural headwinds and execution risks. The company has incurred significant losses since inception, with net losses of $63.7 million ¹⁹ for the year ended December 31, 2025, and expects to incur losses for the foreseeable future. It will require additional funding to finance operations, and if unable to raise capital, may be forced to delay, reduce, or eliminate research and product candidate development programs. The company's limited operating history and early stage of development make it difficult to evaluate its prospects and likelihood of success. The business is highly dependent on the lead product candidate, [225 Ac]Ac-AKY-1189, and its success is contingent on completing clinical trials and obtaining regulatory approval. Preclinical and clinical development is a lengthy and expensive process with uncertain timelines and outcomes, and the novel miniprotein radioconjugate platform may create unpredictable challenges. Product candidates may cause adverse events or undesirable side effects, and results from early-stage studies may not be predictive of future clinical trial outcomes. The time-limited stability of radiopharmaceuticals poses fulfillment and logistical challenges.

Geographic, regulatory, and macro factors identified as constraints include the extensive and unpredictable regulatory approval processes of the FDA and comparable foreign authorities. Changes in U.S. patent law or laws in other countries could diminish the value of patents. The company is subject to U.S. and foreign export and import controls, sanctions, embargoes, anti-corruption laws, and anti-money laundering laws. Disruptions at the FDA and other government agencies, including those caused by funding shortages or global health concerns, could hinder their ability to review and approve new drugs. Healthcare policy changes, such as the Inflation Reduction Act of 2022 and the "One Big Beautiful Bill Act" ³⁸ of 2025, may impact pharmaceutical pricing and reimbursement. The company's reliance on third parties for manufacturing and clinical trials also presents risks, as does the potential for trade restrictions or sanctions on Chinese biotechnology companies, including WuXi Biologics (Hong Kong) Limited, which the company currently engages.

Aktis Oncology faces material risks including significant and expected ongoing losses, with a net loss of $63.7 million ¹⁹ for the year ended December 31, 2025, and an accumulated deficit of $156.6 million ²⁰ as of that date, necessitating substantial additional funding. The company's lead product candidate, [225 Ac]Ac-AKY-1189, is in early-stage clinical development, and its success is uncertain, with preclinical and clinical development being lengthy, expensive, and unpredictable. The novel miniprotein radioconjugate platform may present unforeseen challenges, and product candidates could cause adverse events, undesirable side effects, or have other properties that halt development or limit commercial potential. The company is highly dependent on its ability to obtain a sufficient supply of 225 Ac ³⁹ or other radioisotopes, which are critical components of its product candidates, and disruptions in this supply chain could severely impact clinical development and commercialization. Regulatory approval processes by the FDA and comparable foreign authorities are extensive, time-consuming, and inherently unpredictable, with the potential for delays, additional studies, or denial of approval. The company's reliance on third parties for manufacturing and clinical trials, including contract manufacturing organizations (CMOs) and contract research organizations (CROs), exposes it to risks of non-compliance, delays, or insufficient performance. Intellectual property protection is crucial, but the company does not own or expect to own patents covering the radioactive payload 225 Ac ⁴⁰, and its existing patent portfolio is at an early stage, with the issued U.S. patent for AKY-1189 and any patents from pending applications expected to expire in 2044 ⁴¹. Changes in U.S. and foreign patent laws, as well as the complexities of global patent enforcement, could diminish the value of its intellectual property. Furthermore, the company is subject to stringent and evolving U.S. and foreign laws and regulations related to data privacy and cybersecurity, anti-kickback, fraud and abuse, and export controls, with potential for significant penalties, fines, and reputational harm for non-compliance. Healthcare policy changes, such as the Inflation Reduction Act of 2022 and the "One Big Beautiful Bill Act" ³⁸ of 2025, could adversely affect pricing and reimbursement for future products.

Management's message to shareholders conveys a tone of cautious optimism, emphasizing the transformative potential of targeted radiopharmaceuticals in oncology and the company's strategic position to capitalize on this opportunity. They highlight the clinical and commercial validation of existing radiopharmaceuticals, such as Pluvicto and Lutathera, as a foundation for their novel miniprotein radioconjugate platform. The company's strategic priorities include advancing its lead product candidate, [225 Ac]Ac-AKY-1189, through clinical trials, with preliminary results from the Part-1 dose escalation anticipated in the first quarter of 2027 ⁶. A second key priority is the progression of [225 Ac]Ac-AKY-2519 into clinical trials, expected to initiate mid-2026 ¹⁸. Finally, management is focused on establishing efficient end-to-end supply chain capabilities, including the construction of its own cGMP manufacturing facility, expected to be fully operational in the second half of 2026 ³⁴, and maintaining partnerships with isotope suppliers. They explicitly state that existing cash, cash equivalents, and marketable securities of $226.8 million ²¹, combined with net proceeds of approximately $335.3 million ⁴² from the initial public offering in January 2026, are believed to be sufficient to fund operating expenses and capital expenditure requirements into 2029 ⁴³.